This study proposes use of 10 years of data from an established longitudinal cohort of women to assess whether neighborhood characteristics thought to promote physical activity influence development and progression of measured functional limitations, such as a slow gait or trouble climbing steps. The racially mixed, mid-aged women in live in three diverse Michigan communities and are participants in two population-based studies, Study of Women's Health Across the Nation, Michigan site and the Michigan Bone Health Study. Favorable neighborhood characteristics, i.e., "built environment;" include physical attributes (sidewalks, physical activity resources, proximity of businesses and shops to residences), favorable socioeconomic characteristics and traffic and crime safety. To generate values for these neighborhood characteristics, we will "geocode" existing residential addresses at two time points over a ten-year period. Then, neighborhood attributes associated with these geocodes will be developed from existing public and private data sets. We hypothesize that a built environment unfavorable for leisure and utilitarian physical activity in daily living will predispose to an increased frequency of functional limitations, accompanied by an increase in fat mass, decline in skeletal muscle mass and diminishing physical activity. Aim 1: To determine whether built environment characteristics are associated with level of physical activity, body composition and functional limitations measures in mid-life women cross-sectionally and across time. Aim 2: To determine the role that individual versus community-level demographic variables play in development of functional limitations and in relationships between the built environment and health outcomes. Data from two time points will be analyzed; the first time point (T1) will include data from 1996/7, and the second time point (T2) will include data from 2005/6. Longitudinal analyses will include variables that represent change from T1 to T2 (i.e., calculated as value at T2 - value at T1). Multiple variable mixed models will be used. This study proposes use of data from an established longitudinal cohort of women to assess whether objectively- measured built environment characteristics influence development and progression of measured functional limitations, an area of research that remains largely unexplored. Because the study locales include a gradient of Midwest community types, this investigation will serve as a prototype for future research conducted in the Midwest seeking to replicate these findings. This research will establish foundational insights for designing future large-scale public health investigations and interventions focused on strategies for improving physical activity and functional outcomes. [unreadable] [unreadable] [unreadable] [unreadable]